Democratic fundraising committees outraised their Republican counterparts again last month.

House Democrats’ campaign arm reported it brought in $7.3 million in May, ahead of the Republicans’ $6 million. The Democratic Congressional Campaign Committee now has a war chest of nearly $46 million – about $10 million more than the National Republican Congressional Committee. Neither committee has any debt.

Democrats’ cash-on-hand advantage comes even after the committee reserved an unprecedented $43.5 million in airtime for television ads last month, targeting 36 districts. The NRCC earlier this week reserved $30 million in airtime, $18 million of which will be spent on 17 seats where Republicans see a pick-up opportunity.

Democrats have consistently held the upper hand in fundraising this year, in part driven by an extensive online push. Last month, the committee raised more than $2.3 million from online donations – double the amount of online donations it had received at this point in the 2012 cycle, according to a DCCC spokesman.

“Our supporters believe that it is more important than ever to have leaders in Washington who will end the damaging dysfunction and focus on strengthening the economy for middle class families,” said DCCC Chairman Steve Israel (D., N.Y.) in a statement.

The NRCC declined to comment.

Despite their fundraising success, Democrats’ chances of reclaiming a majority in the House – which would require a net gain of 17 seats – remain slim.

Senate Democrats’ campaign arm also outraised Republicans last month, raising nearly $3 million more in May. The Democratic Senatorial Campaign Committee now has $28.1 million in the bank, about $6 million more than the National Republican Senatorial Committee.

The Democratic committee took out a mortgage on the property it has been leasing for the last decade, but a spokesman said those payments wouldn’t affect how much the committee can spend on races this year.

About Washington Wire

Washington Wire is one of the oldest standing features in American journalism. Since the Wire launched on Sept. 20, 1940, the Journal has offered readers an informal look at the capital. Now online, the Wire provides a succession of glimpses at what’s happening behind hot stories and warnings of what to watch for in the days ahead. The Wire is led by Reid J. Epstein, with contributions from the rest of the bureau. Washington Wire now also includes Think Tank, our home for outside analysis from policy and political thinkers.